Telephone system



April 7, 1925.

TELEPHONE SYSTEM Filed Sept. 12, 1921 2Sheets-$heet l fir Q lrl aflwmmhe. A. YANQCHOWSKI Patented Apr. 7, 1925.

GEORGE A. YANOCHOWSKI, 0F CHICAGO,

TELEPHONE Application filed September To ((Z/ whom it may co-ucem:

Be it known that I, Gnome A. YANG- oiroivs r, a citizen 01" the UnitedStates o'i America, residing at Chicago, in the county of Cook and Stateof Illinois, have inventor. certain new and useful Improvements inTelephone Systems, of which the following; is a specification.

My invention relates to telephone systems, and has to do moreparticularly with divided switchboard systems in which primary andsecondary operators are provided for ii'iterconnecting calling andcalled subscribers lines.

in object of my invention is the provision. of an improved andsimplified divided sw tchboard system operating in connection with acircuit arrangement provided with multiple line lamp distribution,automatic rii'iging' and listening, instantaneous discon ncct and recalland secret service.

Another object ofmy invention is to manually distribute the calls, bymeans of primary operators, to idle secondary operators. 'lhe call\vhen'initiated is made to appear he'tore a plurality of primaryoperators positions by means of the Well l-znziiwn nuiltiple jack linelamp distribution systen'l', which gives a plurality of primaryoperators access to each incoming call.

A feature of my invention is the provision on improved system in whichthe excl ang e switchboard is divided into primary M" d secondarysections, or separate primary ind secondary boards are provided. The

.(i into operators positions which are sag .e section or the switohhomdat which the secondary operniary section oi the switchboard is di- THENOE ILLZL J'QIS, T!) SV'FTCH: BOARD AND SUPPLY COMPANY, OF CHICAGG,

ZLLXNDES, it CGREGEA SYSTEIV'I.

12, 1921. Serial No. 4:99,990.

a )is are located is divided into positions; said positions are providedwith calling; plugs and multiple jael-Is only as is vrell understood inthe art. The answering plugs of the primary operators positions lead andare distributed among the different second ary operators, and when acell appears herore a number of primary operators, the tirst operator toseize the cell merely uses an answering plug Which extends to idlesecondary operator and plugs into an air sivering jack of the callingline, thereby extending the connection to an idle secondary operator.

Another feature oi. my invention is the provision of the lousy signalingmeans whereby when a secondary operator at a secondary position iscompleting a connection to a called line, all the circuits extending tothis particular secondary operatords position from the primary positionsordesignated busy to the primary operator by means of suitable visualsignaling means.

Another feature of my invention is the n'ovision of distinctiveindicating means to the primary operator, should she answer a callsubsequent to the first operator seizing the call; this distinctiveindicating means being; in the form ot a flashing signal so as to notifythe primary operator that the call. has already been answered by anotherprimary operator, and I al o provide suitable means to prevent theattempted connections to he extended to a secondary operator to whichthis primary cord leads. That is, I provide means so that when a primaryoperator connects to a callino' line, which line has alrea been seizedby another primary operator, the call is not extended to a secondaryoperator.

Anotherfeature or my invention is the provision of indicating means forthe sec ondary operator, to whom the call was 0;- tended by a primaryoperator, to notify the said secondary operator tha ans i t, as Wellothers, will fully described he ensuing speoi ill For a betterunderstanding of my invention, reference may be had to the accompanyingdrawings, in which Fig. 1 illustrates the preferred circuit arrangementembodying my invention; and

Fig. 2 illustrates diagrammatically one method of extending the cordsfrom the primary operators positions to the secondary operatorspositions.

Referring now more particularly to the circuit arrangement of Fig. 1, Ishow a calling substation A terminating at the exchange in a linecircuit L, which comprises the usual line relay LR, cut-off relay CO,line signals S and multiple answering jacks AJ. The answering multiplejacks AJ and line signals S appear before different primary operatorspositions, and upon initiation of a call, the multiple line signals arelighted and any one of the operators before whom these signals appearmay answer the call. The switchboard is divided into two sections, aprimary section and a secondary section. The primary section contains anumber of operators positions and each primary operator has appearingbefore her a number of these multiple answering jacks. The positions ofthe primary section are equipped with answering plugs only and answeringsupervisory signals, and the connecting circuit C, as illustrated inrig. 1, comprises a primary operators cord PC, which comprises ananswering plug AP which is inserted into the answering jack Ad toconnect to a calling line. A high resistance test relay TE is providedwhich is energized when the answering plug AP is inserted into theanswering jack AJ of the calling line. The said relay TE uponenergization closes a circuit for the answering supervisory relay AS.The high resistance test relay TE and the answering sleeve supervisoryrelay AS are for permitting only one operator to seize a call, as willbe more fully described in the ensuing specification.

An answering tip supervisory relay AT is provided for the usualsupervisory purposes, and controls the lighting of the answeringsupervisory lamp AL. The primary operators cord PC leads to a secondaryoperators cord circuit SC by means of the conductors a, b, and thesecondary section of the exchange switchboard is equipped with callingplugs only and contains a number of secondary operators positions, eachof which have multiple jacks J so that a call extended to a secondoperators position may be extended to the called line through the agencyof the calling plug C? of the secondary operators cord and the multiplejacks J. The secondary operators cord SC comprises a calling plug GP forconnecting to a called line, and a calling sleeve supervisory relay CSWhich is energized upon the insertion of a calling plug CT into themultiple jack of a called line. calling tip supervisory relay CT is alsoprovided which is energized upon the response of the called subscriberand is for the usual supervisory purposes for controlling the callingsupervisory lamp CL.

An operators listening relay GR is also provided which when energizedconnects the secondary operators set 0 to the cord conductors so thatshe can converse with the calling subscriber. A party-line ring n key BKis provided which controls the connection of ringing generators G, G, (land i and in association with the ringing hey BK I provide a ringingcontrol relay Pai which controls the application of rin 'inc. current tothe called line, and in associ on therewith T also provide aninterrupter relay IR which is intermittently energized and tie-energizedthrough the agency of the constantly rotating interrupter I forintermittently connecting ringing current of the proper generatorfrequency to the call bell of the called line. A calling line lamp C51is also provided which when lighted signals the secondary operator thata call is awaiting her attention. A group relay GB common to a secondaryoperators position also provided for purposes as will be more fullyhereinafter described.

Each circuit C at any one particular secondary operatofs position isprovided with a non-interfering relay These relays have a chainengagement to prevent connecting the operators set to more than one cordat a time. The group relay GB when operated lights the position busylamps BL at each primary operators position that has circuits extendingto one particular second ary operator. If through inadvcrtence more thanone call is extended to a busy secondary operator, the relays OR operateto connect the secondary o1 erators head set to the calls one at a timeas the connections are completed.

To the right of the drawin Fig. l, I show :1 called substation l3tcrn'iinating at the exchange in a line circuit L, comprising the usualline relay LR, cut-off relay (.Q, line signals S and multiple jacks J. I

Fig. 2 illustrates diagramn atically one method which may be employed ind' tributing the primary cords from the pr nary operators positions tothe secondary operators positions, but it is to be understood, however,that other methods of distribution may be used.

In the drawing I illustrate two priman'y operators positions PO and Pt),each having a plurality of answering plugs for use in answering callsfrom subsc iliers lines which terminate at their positions. Thesecondary operators positions SO, 5). SU St) and 30* are provided withen plugs GP for use in extending calls to cede: subscribers lines whichterminate in multiple jacks J7 at each. or the secondary operators"positions. The prnnary operators positions P are provided with a numberor answering plugs AP which I divide into ive groups 0, (Z, c, f and g,and as herein shown, the first group of plugs AP from the primaryoperators positions P) lead to the secondary operators positions SO andterminate in the calling plug CP. The second group (Z leads to thesecondary operators position SO, the third group 6 leads to thesecondary operators position S0 the fourth group leads to the secondaryoperators position i. O, and the fifth group 7 leads to the secondaryoperators position S9 The primary operators position PO is also providedWith answering plugs AP divided into similar groups 0, d, e, f, and g,and lead, respectively, to the secondary operators positions S0, S9, S030'' and 30*. The secondary (n crators position is provided with a grouprelay GR which is energized at the time that the secondary operator isextending a connection to a called line to light a busy signal lainp BLat each prin'iary operations position that has access to this particularsecondary operator, so that none of these operators will extend :alls tothis secondary operator While she is extending a connection to a calledline.

From the above description it may be readily seen that the calls ill bethus evenly distributed among; the diii'erent secondary operators. Theprimary ope 'ators distribute the calls manually to the (littercntsecondary operators. The line lamp distribution makes all callsaccessible to each priniary operat r, thereby permitting any primaryopers or to answer any call and extend the connection to any idlesecondary operator that she has access to. This makes it possible forone primary operator to answer all calls at night Without moving fromher position.

Having: described in general the apt ara tus embodying my invention, Iwill noiv de-,

scribe in detail the operation of the circuit as illustrated in Fig. 1.

Assuming now that the subscriber at the falling substation A initiates acall, the removal of the receiver thereat establishes an energizing;circuit for the line relay LR. ot the line ci cuit L. The line relay LRupon energization closes its alternate contact to light the multipleline signals 8 to signal the primary operatorsbetore Whom. the insweringjacks A5 are positioned, and one of the primary operators seizes thecall by inserting an answering plug AP leading to an idle secondaryoperators position into the answering jack AJ. The insertion of he plug;AP into the jack Ail closes an energizing circuit for the highresistance test relay TE of the primary cord PC and the cut-off relay C0of the line circuit L,

nectec plug All and jack Ad to ground through the winding of the cut-oilrelay C0. The-relay AS upon energization closes its alternate contact 5establishin a substitute energizing circuit for the relay AS,independent of the alternate contact oi.

the test relay TE, this substitute circuit being traced from batterythrough -tl1B-Wl1'i(l mg 0-; the relay AS, its alternate Contact 1 5,cond ctor z, normal contact 3 of the relay Ll), the sleeve contacts ofthe connected plu a? and jack All to ground through the winding of thecut-oil relay CO. The relay C0 is also energized to open the circuit ofthe line relay LR and the line re-. lay LR tie-energizing brings aboutthe eli'acement of the multiple line signalss. The

apswering tip supervisory relay AT is also. energized over a circuittraced from battery through the upper winding 01 relay AT, normalcontact atlot relay Ll), tip contacts of the connected plug AP and jackAll, i

through the substation, baclr through the ring contacts of the connectedplug AP and jack All, normal contact of relay LD to ground through thelower winding of relay AT; and the energization of the relay AT preventsthe premature lighting of the answering supervisory lamp. AL. The relayAS upon energization closes its alternate contact 6, establishing anenergizing.

circuit for the operators listening relay OR of the secondary cord'tlCot' the idle secondary operators position, traced from battery throughalternate contact 6 of the re lay AS, conductor 7, normal contact 8 outthe ca ling sleeve relay CS of the secondary cord SC, conductor 9, thewinding 10 of the operators listening relay OR, conductor ll, throughthe series contacts 12 ot' the chain or relays OR of the secondary openators position, conductor 13-3, normal contact 12 of the relay OR,conductor 14, to ground at normal contact 15 of the group relay GR,which relay GR is common to the secondary operators position to whichthe call has been extended by the primary operator. T he relay ORenergizes over this circuit and upon energization opens its normalcontact 12, opening the initial energizing circuit 01": the relay QR,but a substitute circuit is established for the said relay Which lit)lift) may now be traced from battery through the lower winding 16 of therelay OR, alternate contact 17 of the relay OR, conductor 18, to groundat normal contact 19 of the calling sleeve supervisory relay CS. Theclosing of alternate contacts 20 and 21 of the relay OR connects thesecondary operators set 0 to the cord conductors, and the closing ofalternate contact 22 closes an energizing c"cuit for the call indicatinglamp CA, raced from battery through alternate contact 22 to ground,through the lamp CA. The lamp CA. is lighted and indicates to thesecondary operator that a call has been extended to her position andalso indicates to her that her operators set has been con -ceted to thecord conductors and she now ii quires the wants of the callingsubscriber at the substation A.

The closing of alternate contact 22 also closes an energiz'ug circuitfor the group relay GR, traced from battery through alternate contact22, conductors and El to ground through the winding of re ay GR. Thegroup relay Git is common to the secondary oaerators position of whichthe cord circuit is one, and energizes when a call is extended to thesecondary position, and the closing of alter rate contact. of the gro'uprelay Git upon its energiraation establishes an energizing circuit forthe primary operators group busyine" relay Gil of the primary operatorsposition that OX- tended the call to this secondary operator traced fromground through alternate contact 15 of relay Git, conductor 26, throughthe winding of the relay GB to battery. lilac-h primary o1 eratorsposition is proided with a number of primary operators" group busyingrelays Gil, which are common to the cords at the primary operatorspositions that have circuits that lea d to the secondary operatorsposition. Each primary operators position is provided with a group relayGB, which group relay GB is common to all of the primary cords PC thatextend to this secondary operators position to which a call has been,XtODtlGCl by the primary operator. The relay Gil upon energizationcloses its alternate conact 27 and establishes a circuit for the busylamp Bil from battery through alternate contact 27, through the lamp BLto ground. The busy lamps BL at the other primary operators positionsare also lighted, thus advising the primary operators of the busycondition of the secondary opcrators posi tion, and this busy conditionremains until the secondary operator has extended the connection thecalled line.

(he operators haying been connected to the cord conductors as abovedescribed, she now inquires the 'ants of the calling subscriber atsubstation A. Assuming that it is the called subscriber at substation l3that is wanted, the operator tests the multiple jack J appearing at herposition to its idle or busy condition, and if the line is busy she willreceive the customary has click. Assuming that the line is idle sheinserts the calling plug GP into the n'iultiple jack J oi the calledline, and this act clo a series energizing circuit for the callingsleeve supervisory relay CS and the ciiit-oli' relay Ct) of the linecircuit L of the called substation B, the circuit being traced frombattery through the winding of the relay CS, conductor 28, the sleevecont. cts of the connected plug JP and jack J to ground the cut-offrelay CO. The calling sleeve relay CS upon energization opens its normalcontact 19, opening the energizing circuit of the operators listeningrelay ()lt through its holding winding 16, and the relay OR nowtie-energizes and the opening of its alternate contacts and 21disconnects the operators set 0 from the cord conductors. The opening ofalternate (501% tact o'l" relay OR also ell-aces the call indicatingsignal CA and the opening of alternate contact 22 opens the energizingcirc'uit of the group relay GP. The group relay Git is now de-energ'izedand the opening oi its alternate contact 15 opens the en ergizingcircuit of the group relays GB. The group relays Gil tie-energizing opentheir alternate contacts to ell-ace the busy indicating lamps BL,notifying the primary operators that the secondary operator has extendedthe call to the called line and is now ayailable so that otherconnections may be extended to her position. The closing of alternatecontact 19 of relay US also closes an energizing circuit for thesupervisory lamp CL from battery through the lamp Cl), normal contact 36of relay 'l. conductors and to ground at alternate contact of relay CS,the said lamp remainlighted until the called subscriber answcrs.

The secondary operator now depresses the proper ringing key plunger ofthe ringing key BK to impress the proper ringing generator current overthe called line to ring the call bell atthe called substation ii. Thedepression of the ringing key plunger associated with the selectedgenerator 'liequeney momentarily operates the end springs of the ringingkey. T he closing ol alternate contact ot the end springs establishes anenergizing circuit for the ringing control relay RC traced from batterythrough the winding of the relay RU, conductor 31, alternate contact 30of the end springs, conductors 32 and 33, to ground at alternate contact19 of the relay CS. The relay RC upon energization closes its alternatecontact 3% establishing a locking circuit for itself traced from batterythrough the winding of the relay RC, alternate com tact 34;, conductor35, normal contact 36 of the calling tip supervisory relay CT,conductors 32 and 33! to groinid at alternate contact 1:) of the relayCS. The closing of alternate contact 3'? of the relay RC est-ablishes anenergizing circuit for the interrupter relay TR, traced from batterythrough the interrupter 1, through the winding of the relay 1R,conductor 38, alternate contact 3'? of the relay RC, conductor 39,normal contact of the end springs, conductor 32 and 3 3 ground atalternate contact 19, oi the relay CS. The relay TB is intermittentlyenergized and cle energized over the circuit as just traced, tointermittently connect ringing current o cr the called line, the ringingcircuit being traced from the ungrounded pole of the generator (it,which We Will assume is the selected generator "frequcncy, the closedcontact of the ringing hey plunger over the rin ing conductor il), alternate contact 4:1, of the! relay IR, the tip contacts of: theconnected plug l and jacl: 5, through the condenser and call bell of thcalled substation B back through the ring contacts c cl at alternatecontact 412 of the I ie called SlllLZCllllQl' at the subin response tohis call signal removes his receiver from the switch hook and git rdpositions, an energizing circuit is establislicd tor the calling tipsupervisory relay CT, 1 upper winding of the relay CT, alternate contactof the relay CS, normal contact ll of the relay IR, tip contacts or theoonnccted plug GP and jack J, the now closed contacts of the substationswitch hook of substation B, back through the ring contacts of theconnected jack J and plug P, nornnw coi'itact 452 of relay IE, to groundthrough the lower winding Off the relay UT The rela T upon energizationopens its act which opens the locking or the rin 'ing control relay RC,and aging control relay RC is (ls-energized and the opening oi itsalternate contact 37 the enci-"izing circuit of the relay TR,

the rehiy remain at normal prerents trurther application or ringingcurrent o the called llnc. The opening 0t normal contact 36 ot' therelay GT also opens the cirsupervisory lanip CL and the subscricers attie tat1onl3 have finreplace th ir the connected jack J of the plug 1CDthe relay IR is in one of its de-enertraced from battery through thevisory lainp CL is efi acecl and notifies over the heavily receiversupon the respective SWltOllllOOliS.

the answering tip supervisory relay AT, and the closing of its norn'ialcontact 46 establishes an energizing circuit for the link tlisconnectrelay Ll), traced from battery, through the'winclingot the relay LD,conductor T7, normal contact 46 01 the relay AT, concluctor lfi,alternate contact 49 of the relay AS, conductor 50 to alternate con tact19" of the relay CS. The link disconnect relay upon energization opensits .norinal contact3, opening the initial energizing circuit of theanswering sleeve supervisory relay AS, but a substitute energizing'cincuit is closed for the said relay traced from battery through theWinding of the'relay AS, alternate contact 5 of the relay AS, conductor2, alternate contact 3, oil" the relay LD, conductor 51, alternatecontact all of the relay AS, conductor 50, to ground at al ternatecontact 19 otthe relay CS.

The closing of normal contact 5201? relay AT closes an energizingcircuit for the answering supervisory lanip AL, :troin battery throughthe lamp Abnormal contact of the relay AT, conductors 53 and 47, normalcontact 46 of'relay AT, conductor as, alternate contact 49 oftherelay'AS, conductor 50 to grounclat alternate contact 19 of the relayCS. The lighting of the answering supervisory lainp AL over this circuitnotifies'the primary operator that the calling subscriber at substationA has replaced his rcceiyer. The closing of alternate contactbtof therelay LD establishes an energizingcircuit for the high resistance relay55, traced from battery through *the line, and the'opening of normalcontact 0 Orr-1193mm relay-LDperniits the deenergization of the cutoftrelayCQthus placing the line circuit'L otthe-cal'ling subscriber A'at'normal so that should the subscriber Wislrto recall he may 'do so eventhough the answering plug AP remains in the pol; AJ. The relay55-energ'izes to ground through the cut ofi" relay CO of the nowrestored line c-ircuitL, but clue to the high resistanceot the relay 55,the out oft relay CO reinains at'nornial anddoes not make the jacks 'JOfthe callingline test busy.

The called subscriber at the substation 3 replacing his receiver uponthe svvitclr hook opens the energizing circuit of the calling tipsupervisory relay CT. The said relay restoring; to normal again closesits normal contact 36 closing the energizing circuit for the callingSllPGl'VlSOly lamp CL to ground at alternate contact 19 of relay (TS.The supervisory lamp All of the pri: inary o erators position is nowlighted, and tl e calling supervisory lamp CL the secondary operatorsposition is lighted, llll ll," eating to the tvvo oierators that theconversation has terminated, and that the subscribers at the callinesnhstatio A and the called substation B have replaced their receivers.The primary operator now withdraws the answering plug AP from the jackAll openin the energizino; circuit of relay Relay 55 d -energizinecloses contact 6L thus causina' the lamp AN to glow at the secondaryoperators position. The secondary operator now Withdraws plug UP fromjack J, and the Withdrawal of the calling 7 Cl? from the multiple jack Jof the called line by the secondary operator opens the series energizingcircuit of the calling sleeve relay of the cut off relay CG.

is The sleeve relay CS (lo-energizing opens its alternate contacts 19and 19. The opening of: alternate contact 19 etl'accs the supervisorysignal CL the opening of alternate contact 19' opens the holdingcircuits of the linl: disconnect relay Ll) and the answering supervisoryrelay AS. The appara us used in establishing the connection between thesubstation A and the substation ll is now at normal and available foruse in est "dishing other connections.

Assuming that conversation has terminated and the subscribers A and Bhave replaced their receivers upon their respective svvitchhooks asabove described. and before the plugs AP and GP have been re moved fromtheir respecti e jacks, that the subscriber at the calling substation AWishes to recall, the removal oil? the receiver at the recallingsubstation it closes a circuit for the linerelay LB, and the line relayLR energizing; closes a circuit for the multiple line s gnals S, and thesame primary operator may answer the recall, or another primary operatormay seize it to the exclusion of the other primary oper tors.

iissinningthat the same nrimary operator seizes the recall thatoriginally established the connection for the calling;' subscriber A,she now Withdraws the answering plug AP from the connected jack T andthis ivith- 1/ the drawal allows the relay 55 to restore and therestoration of the said relay closes a circuit through the disconnectlamp AN oi the secondary operators cord circuit SC that established theconnection to the called line, the circuit being traced from batterythrough the lamp AN, conductor 60, normal contact 61, of the relay 5?conductor T, normal contact 416 of the relay ji conductor 48, alternatecontact or the relay AS, conductor 50 to ground at altcrnab lie contact19 of the sleeve relay i lighting of the disconnectlamp All notii" thesecondary operator tha' the prin'iar r onerator has Withdrawn thezuasiverin3- plug Al from the jack Ad of the calling line as previouslydescribed. The primary operator 110W inserts an ansi'vcring nlu; intothe jack All and the connection is ca ended as before mentioned.

Should the calling sul'iscriber at the Sllllstation A initiate a call,the removal oi the QCCIVQI at the substation brings about the liehting;of the line signals S as prerioruily described, and assuming that thecall is answered by the primary operator vxho handled the calloriginally, nov. should another 1')1'l]lltl:y' operator of a primarycord PC insert an answering plug into the multiple answering jack oi thecalling line after the call has been seized by the first operato theinsertion of the plu l? ot the second Pl'lil' y cord PC brings about theone tion of the answering tip supervisory ix. .atl of this secondprimary cord, and t, closing of alternate contact 52 oi the relasupervisory lamp fill traced from b2: tl'u'oue'h the said lamp,alternate c nla conductor 70, normal contact 71 o l, '3 v. 4 .3; LR)rotating ll interrupter I. the interruliiter l causes the up supervisorylamp All ot the sci-,-

sn'erit ond primary cord to flash indicatii'ig to priinarv operator ofthe secon l prii cord l C that the call has been seized l anotherprimary operator. The secon a op. tor is not coni'iected to thecallini'" 1.

over the second primary cord PC that he? been inserted into the calling;line as the test relay 'llll oi? the second cord energize, due to thelow resistance in ot the relav All of the first primary co a d the relayTE 01 the second prinia cord in shunted and in failing; to 01192 circuitis established for the ans sleeve supervisory relay AS of the primarycord and said relay I: 1% oi" the second primary cord remains at normaland as its alternate contact 6 is not closem tinoperatoi"s listeningrelay OR of the seiondary cord 90 is not operated and e1 "ors set U ofthe secondarv cor-z.

is not connected. i

The relay energizes upon the resta rtion o'li' the switch hook at thecali' station and when the relay Ll) one held up to ground through theca. lay CO, and should a calling tation A. ntiat-e a recall and otheroperator seize the recall, the relay bscri secondary cord PC and" SCrespectively are lighted.

The primary operator in response to the signal AL withdraws. the. plugAl fronr the. jack 'AJ and brings about the lighting of the disconnectlanip AN at the secondaryoperators position giving her a visualindication that the'answering plug has been withdrawn, and theadditional lighting of the supervisory signal CL notifies her thatdisconnection has taken place at-the primary end, andthat the calledsubscriber has replaced his receiver and that the plug 01. niaynow bewithdrawn.

The initial energizing circuits of the oporators listening relays OR ofa secondary operators position. extends through a chain relayarrangement in which the-energizing circuits through the windings 10 ofthe operator s relays are carried through a series connection throughthe normally closed contacts i2, 152, etc, cit-the operator s relay.ll-l. New should two prin'iary operators happen to extend connectionsto one secondary opcuxatcr the same time, the relay OR of the secondarycord to which one of the primary operators has extended. the connectionfrom a primary cord of her position operates'over a circuit aspreviously described, through the chain'relay arrange uient'inchidingcontacts 12, 12,-etc., oi other relays OR. Upon the energization or relay OR its contact 12' is opened and should a second. primary operatorextend a'conuection to the same. secondary operator at the same time asthe first, the operators relay UR oi this second selected secondary cordwill fail. tooperate as the series chain connection through contacts12,12, etc, is broken at the contact 12" of the relay OR of the firstcord, and thus relay Oliot this second cord will not "energize due tothe break in the series contact connection and the operator set will notbe connected, and it will thus be seen that only one call'can beextended to a secondary'operator at the same time. Relay GR energizingalso opens the original energizing circuits for relays OR. If severalcalls are extendedto one secondary operatorsposition they'will beautomatically connected to the secondary opcrators set one at a time asshe completes the connections. The. call lamps are not lighted untiltliecorresponding relay OR is energized. I

While I have illustrated my invention operating inconneetion with aspecific circuit arrangement,it'is"tobe understood that board dividedinto positions, a

my invention is adaptable to othe systems and that changes andmodifications will readily suggest tl'i'einselves to those skilled inthe art, and. I therefore aim to cover all such changes andmodifications as conic withinthe spirit and scope of the appendedclaims.

Having described my irwention what I claim as new and desire tosecure-by Letters Patent l. A telephone system including aswitchboard'divided into'positions, a calling line appearing in multipleanswering terminals at a plurality of: said positions, a secondswitchboard divided into positions, circuits extending tronione of saidpositions upon said first board to. positions upon said'second board,the answering ends of said circuits being located at said firstswitchboard,

and the calling ends of said circuits being located at said secondswitchboard, an operators head set at one position upon saidsccond'board, means responsive to the direct connection ot one of saidcircuits with any one of the multiple answering terminals of saidcalling line to connect said operators set to said circuit, andsubscriber controlled means for disconnecting his line from saidcircuit.

2. A telephone system including aswitchcalling lino appearing inmultiple answering terminals a plurality of saidpositions, a secondswitchboard divided into positions, a called line appearing in multipleaclitsonsei'eral ct said last 'POSltlOll-S, circuits extending;

'iioni or" said POSliJlODS upon said first board to posi.,ion.s uponsaid second board, the answering ends ot said cu" 4-1 l rim 126111 tilocated at said first switchboarc, an.d."the

' callin ends said circuits beinc' located at b x: J

said second switcl'iboard, an operators at one position otsa d secondswitchboard,

means responsive to the direct connection oi? one of said circuits withanyone oi? said multiple answering terminals oi said calling line toconnect said operator s set thereto,

means responsive to the connection of said circuit to said called lineto disconnect said operatofis set from said circuit, and subscribercontrolled means for automatically disconnecting his line from saidcircuit.

3. A. telephone, system including a switch board divided intopositions,-a calling line appearing inanswering jacks at a plurality ofsaid positions, a second switchboard divided into positions, circuit-sextending: from one of said positionsupon said first board to positionsupon said second board, the

answering ends of said circuits being located at said first switchboardand the calling ends of said circuits being located at said secondswitchboard answering ternnnals for said circuits at said firstswitchboardadapted to make physical connection with said sivitchcallingline a plurality 1 1. nooard ciing terminals for sa'd circuits at saidfirst switchboard adapted to make 'li physical connection with saidansu'eri U jaciis,

nnecting said answermanual means for co ing terminals to said answeringjacks Whereby calls are manually distributed to the operators at thesecond of said S\ .l '"llbOtIl(lf an operators telephone set at itssecond sritchboard, means for automa-ically connecting said operators toc 1010 to one of said circuits when its an or lg terminal is connectedto one of suit answering jacks to connect said onerators at said secondcircuit with switchboard in conversati the calling line, means foroperators at said first snvrcl'iboaro when the operators are idle atsaid second switchboard, and subscriber controlled means fordisconnecting the subscribei"s line from said circuit.

A telephone system including a s vitchboard divided into positions, acalling line appearing in answering jacks at a plural it-y oi saidpositions, a second switchboard di ided into positions, a called lineappearing in multiple jacks on several of said last positions, ircuitsex ending" from one o't said positions upon said first card to positionsupon said second board, answering terminals for aid circuits at saidfirst switchboard adapted to make dir-ct ihysical connection with saidanswering jacks, manual means for connecting said answering terminals tosaid answering jacks whereby calls are manually distributed to theoperators at the second oi said switchboards, an operatn"s to ephone setat said seconc switchboard, means r automatically connecting saidoperators to one of said circuits when its a-nsu 'eri to animal isconnected to one of said ansn'erii jacks to cor nect said operators setat said second switchboard in conversa "cu t with tienal c' the callingline, means tcr indicating to the switchboard operators at said firstwhen operators are idle at said second switchboard, calling terminalsfor said circuits db said second switchboard, manual means forconnecting said calling terminals to said multiple jacks to completeconnections, and subscriber controlled means for automatically freeing asubscribers line from one of said circuits.

6. A telephone system incluoinr; a sn'i' board divided into positimis, 1

appearing in ansn 'ing terminals ng u'lieth r or not ;he operators atsaid SQ!- ond sritcl iboard are busy or idle, an op said circuits atsaid second for automaticall, conanswering end of said circuit one of danswering term Jcriber controlled means tor t re subscribefis line fromone ie to b.

u; ph'ine system including a switchboard divided into posicioi s, acalling line appearing in answering terminals at a plurality of saidpositions, a second sivitchlmard divided into positions, multiple jacksa said second s ritchboard, circuits extending from. one of saidposit-ions upon said first board to positions upon said second board,manual means for directly and ph -Jsicall'v connecting: one of saidircuits to said calling; line, an operators set at one position of saidsecond switchboard, iutomatic means at said position for connecting anddisconnecting the opcratofis set from the circuits that terminaljethereat when he circuits are counectml to said answering terminals andsaic inultijacks resgectivcly, autoiratic means for pr venting thconnection of said operators set to more than one circuit at saidposition at one time, and subscriber controlled means to autoi'naticallfreeing a subscril's ers line from one of said circuits.

8. A telephone system including a board divided into positions, acalling appearing' in answering terminals at rality of said positions, asecond FEW .7 board divided into positions, a called line appearing; inmultiple jacks on serea'al of said last positions, circuits extendingfrom one oi said positions upon said first board to positioi-i upon saidseco d b aid and ed to h we is physical connection said ansiv an ope'ators ii-(lifi phone at one means in said one circuit at said oneposition of said first. board forautomatically freeing a line from saidcircuit.

9. A telephone system. including a switchboard dividedl'into spositions, a calling line appearing in answering terminals at aplurality of said positions, a' second: switchboard divided intoposit-ions, circuits extend-- ing from: one of said positions upon: saidfirst board to positions upon said; second board and adapted to havedirect physical connection: with; said. answering terminals, manual:means for connecting said circuits to said answering terminals, an:operators set at said second switchboard. for said circuits, means forautomatically connecting said operators set toone of said circuits whenthe same is: connected to one. oi? said answering terminals, means atsaid first switchboard for. indicating. to air operator thereat-whetheror-not operators at certain of said: positions. on said. secondswitchboard are idle. or busy, and; subscriber controlled. means in:said: one circuit for. freeing the? subscribefs line: from said. onecircuit.

10. A telephone system includinga-switchboard divided into: positions,acalling line appearing in: answering: terminals at a: plurality of saidpositions, a second switchboard divided into positions, circuitsextending from one. of said. positions upon said first board topositions upon said. second board and adapted tohave physical connectionwith said. answering: terminals, means at said first switchboard forindicating; to

the operatorat one of. the positions of: said connect to theanswering-terminals to dis tribute the: calls toidl'e: operators at saidsecond switchboard, an:v operators set at said second switchboard forsaid circuits, auto-' matic means for connectingsaid 'operators set to:one or". said circuits upon-the connection of said circuit to oneoi'said answering terminals-L providin-gfsaid' operators set is notalready connected to another of said circuits, and subscriber controlledmeans for freeing a subscribers line from one of said circuits.

11. A telephone system including a switchboard divided into positions, acalling line appearing in answering terminals at a plurality of saidpositions, a second switchboard divided into positions, circuitsextending from one-of said positions upon said first board to positionsupon said second board, means for automatically preventing operativeconnection of more than one of said circuits at one time to said callingline in response to a call on said line, and a supervisory gnal operableintermittently to notify an. operator connecting" a: circuit to saidcalling line subsequently to the connection of another circuit to saidcalling line by another operator that. the said other operator hasseized. the calL- 12.. A telephone system including a. switchboarddivided into positions, a calling line appearing in answering terminalsat plurality of said positions, a second switchboard divided intoposit-ions, circuits extending from one of said. positions upon saidfirst board topositions upon. said. second. board, test means for: saidcircuits whereby the first circuit tozoperatively connectv to saidcalling line in response to a. call. thereover will prevent a secondcircuit from. connecting to said calling. line, a supervisory signal,means for intermittently operating said superv-isory signal to indicateto the. operator that the call has. been. answered by; another operator,and: means for causing said sig 'al to operate. continuously to signal.for a. disconnection. H

13.- A telephonev system including a calling subscribers lineterminating in multiple answering terminals; and. multiple lamps, aplurality of cord circuits at difierent operators" positions forconnecting to said calling line, test means for preventing theoperatives connection of. more than one oi said cord circuits to said.calling line at the same time in response to a-call over saidline,asignal,v means for operating said signal inte-rmittently if twocord circuitsare connected tosaid line iuattempting to answer a call,and means for causing, said signal tor operate continuously to signalfor a disconnection.

14. telephone system including a calling subscribers line andza calledsubscribers line, a circuit extending through two operator's" positionsfor connectingsaid calling subscribers line to said called subscribersline, a supervisory lamp at each of said positions, means at one of saidoperators positionscontrolled by a subscriber. for freeing hisv linefrom said circuit and for light ing the supervisory l'am'pat the saidposition, means responsive to-the disconnection of the terminalof saidcircuit. from the said calling line for operating the supervisorysignal" at the other of said positions, another circuit for connectingto said calling line, and automatic means for intermittently operatingsaid signal at said one operators position it said other circuit isconnected to said calling line prior to the connection of said firstcircuit to notify the operator at said first cord that the call hasalready been answered.

15. A telephone system including a calling subscribers line and a calledsubscribefis line, a link circuit having an answering terminal forconnection to said calling subscribers line and a calling terminal forconnection to said called subscribers line, a pair of tromagnct meansoperative when the operator removes the answerlng terminal of said linkcircuit from the jack of said line to operate said signal.

17. A telephone system including a switchboard divided into positions, acalling line appearing in answering terminals at a plurality of saidpositions, a second switchboard divided into positions, a called lineappearing in multiple jacks on several of said last positions, circuitsextending from one of said posit-ions upon said first board to positionsupon said second board and having manually controlled connectionterminals adapted to be directly and physically connected to saidanswering terminals, an operators set at one position of said secondswitchboard, means responsive to the physical connection of one of saidcircuits to said calling line to connect said operators set thereto,means responsive to the connection of said circuit to said called lineto disconnect said operators set from said circuit, and automaticringing means for signaling the said called subscriber.

18. A telephone system including a switchboard divided into positions, acalling line appearing in answering acks at a plurality of saidpositions, a second switchboard divided into positions, a called lineappearing in multiple jacks on several of said last positions, circuitsextending from one of said positions upon said first board to positionsupon said second board, answering terminals for said circuits at saidfirst switchboard,

manual means for connecting said answering terminals to said answeringjacks whereby calls are manually distrbuted to the operators at thesecond of said switchboards, automatic supervisory means for indicatingto an operator at said first switchboard connecting to said calling linesubsequently to another operator at said first switchboard that the callhas been answered by said other operator, means for indicating to theoperators at said first switchboard when the operators are idle at saidsecond switchboard, calling terminals for said circuit at said secondswitchboard, manual means for connecting said calling terminals to saidmultiple jacks to complete connections, and automatic ringing means forsignaling the said called subscriber.

19. A telephone system including a switchboard having a plurality ofpositions, subscribers lines terminating in multiple answering jacks ata plurality of said positions, a second switch board having a pluralityof positions, multiple jacks for said lines at said second switchboard,groups of circuits extending from positions at said first switchboard topositions at said second switchboard, terminals for said circuits atsaid first switchboard for connecting said circuits to calling lines,means for preventing the operative conection of more than one circuit toa calling line at the same time,

supervisory means for indicating to operators connecting to a callingsubscribers line, subsequently to the connection of another operator,that the call has been answered by said other operator, busy means toadvise the operators at said first board which operators at the secondboard are busy, such manual distributing means in connection with themultiple line lamp distribu tion making it possible for the calls to beanswered by different idle operators at said first board and to beextended to idle operators at said second board.

Signed by me at Chicago, in the county of Cook and State of Illinois,this 10th day of September, 1921.

GEORGE A. YANOCHOVVSKI.

